Mar. 31, 2016, 1:57 p.m.

As debate over the proposed minimum wage bill continued inside the state Capitol on Thursday, an incident that occurred during a rally outside the building drew fire and police officials and quickly raised alarm.

The Sacramento Fire Department initially described the event as a "mass casualty incident," adding to the concern.

Mass casualty incident at state Capitol. Total of 7 patients so far with medical complaints. Unknown causes pic.twitter.com/wjXGPZ5pf5

About 7,000 people were gathered outside the Capitol for a rally with Franklin Graham, son of evangelist Billy Graham, according to Chris Harvey, public information officer for the Sacramento Fire Department.